Hitachi YUTAKI Series - Page 45

43
Accessories hydraulic installation
SMGB0066 rev.0 - 12/2009
Water pipe
installation
Service Manual
2

Return
Input
Mains
water input
Recirculation
H.S.W.
Ref. Name

Sanitary safety valve unit

Non-return valve

Circulator

Recirculation pump

Shutoff cock

Drain

Drain valve

Heating coil

DHWT(200/300)E-2.5H1E DHWT(200/300)S-2.5H1E
01
0.20.5
10
100
20
50
200
500
5
10
25
C
p
=
m
3
/h
mbar
01
0.20.5
10
100
20
50
200
500
5
10
25
C
p
=
m
3
/h
mbar

Thesafetyvalveunitwillttedatthesanitarywaterinstallation. -
A pressure reducer must be placed in the DHWT installation. The nominal pressure of the safety unit will be 8 bar. -
When the main pressure is more than 6 bar a pressure reducer should be installed. -
The water discharge during heating (expansion) is normal. The volume of this discharge can be up to 3% of the storage -
tank’s capacity.
Thepressureregulatordevicemustbeworkingregularly,dependingonthequalityofwater,inordertoremovethe -
lime’s deposits and verify that it is not blockade.
A water leakage in the pressure protection device can exist. The discharge pipe should be always open to the -
atmosphere,freeoffrostandincontinuousslopetothedownside.
Dielectricbushesmustbettedattheinputandoutputsanitarywaterandatthetankcircuitconnections. -
Emptying the DHWT: Close the main inlet water valve and open the relief valve of the security water group. -